#!/usr/bin/bash

[[ -z "$SNIPPETS" ]] && echo "SNIPPETS directory undefined" && exit 1

snippet() {
  > "$SNIPPETS/last"
  while IFS= read -r line; do
    echo "$line"
    echo "$line" >> "$SNIPPETS/last"
  done
}

snip() {
  if (( $# == 0 ));then
    snippet "$@"
    return $?
  fi
  local name="$1"
  shift
  local path="$SNIPPETS/$name"
  
  if [[ -r $path ]]; then

    local buf="$(<$path)"
    if [[ -s /dev/stdin ]]; then
      local in="$(</dev/stdin)"
    else
      local in=""
    fi

    if [[ $# = 0 && -z $in ]]; then
      echo "$buf"
      return
    fi

    if [[ $# > 0 ]]; then
      local -i n=1
      for arg in $@; do
        buf=${buf//\{$n\}/$arg}
        ((n++))
      done
      echo "$buf"
    else
      while IFS=$'\n' read -r argline; do
        if [[ -n $argline ]]; then
          IFS=" " snip $name $argline
        fi
      done
    fi

  fi
}

snip "$@"